CVE-2026-24919: Huawei EMUI DOS Vulnerability

CVE-2026-24919 Overview

CVE-2026-24919 is an out-of-bounds write vulnerability [CWE-787] in the Design for X (DFX) module of Huawei EMUI and HarmonyOS. A local attacker with low privileges can trigger the flaw to corrupt memory outside the intended buffer boundaries. Successful exploitation affects device availability, typically resulting in a denial of service condition.

Huawei disclosed the issue in the February 2026 security bulletin. The vulnerability requires local access and does not require user interaction. Confidentiality and integrity are not impacted, but availability impact is rated high.

Critical Impact

A local, low-privileged attacker can write outside allocated memory in the DFX module, causing availability loss on affected EMUI and HarmonyOS devices.

Affected Products

• Huawei EMUI 12.0.0, 14.0.0, 14.2.0, and 15.0.0
• Huawei HarmonyOS 4.0.0, 4.2.0, 4.3.0, and 4.3.1
• DFX module within the affected operating system builds

Discovery Timeline

• 2026-02-06 - CVE-2026-24919 published to the National Vulnerability Database
• 2026-02-06 - Huawei publishes the February 2026 Huawei Security Bulletin
• 2026-02-10 - Last updated in NVD database

Technical Details for CVE-2026-24919

Vulnerability Analysis

The vulnerability resides in the Design for X (DFX) module, a component used in Huawei's mobile operating systems for diagnostic, logging, and reliability instrumentation. An out-of-bounds write occurs when code writes data past the boundary of an allocated buffer. The flaw is classified under [CWE-787], one of the most prevalent memory safety weakness categories.

Exploitation requires local access to the device and low privileges. No user interaction is required, and the attack does not cross a privilege boundary outside the affected component. The impact is limited to availability, meaning the most likely outcome is a system or service crash rather than code execution or data exfiltration.

Root Cause

The root cause is missing or insufficient bounds checking when the DFX module writes to a memory buffer. When attacker-controlled input drives the size or index of a write operation, adjacent memory regions can be overwritten. This corrupts kernel or process state, leading to abnormal termination of the affected component.

Attack Vector

The attack vector is local. An attacker must execute code on the device with at least low-level user privileges, for example through a malicious or compromised installed application. The application then invokes the vulnerable DFX interface with crafted parameters that trigger the out-of-bounds write. Huawei has not published technical details of the triggering input or the affected function. Refer to the Huawei Security Bulletin for vendor guidance.

Detection Methods for CVE-2026-24919

Indicators of Compromise

• Unexpected reboots, kernel panics, or service crashes on EMUI or HarmonyOS devices running affected versions
• Crash dumps or tombstone files referencing the DFX module after installing or running untrusted applications
• Repeated application launches preceding device instability from a non-system package

Detection Strategies

• Inventory managed mobile devices and identify any running affected EMUI or HarmonyOS versions listed in the February 2026 Huawei bulletin
• Review Mobile Device Management (MDM) telemetry for installed applications that request unusual diagnostic or system-level interfaces
• Correlate device crash reports with recent app installations to identify candidates for further analysis

Monitoring Recommendations

• Enable MDM crash and reliability reporting for Huawei devices and forward events to a centralized log platform
• Alert on repeated DFX-related crashes or tombstones across a fleet, which may indicate active exploitation attempts
• Track patch level compliance against the February 2026 Huawei security bulletin in asset management tooling

How to Mitigate CVE-2026-24919

Immediate Actions Required

• Apply the February 2026 Huawei security update to all affected EMUI and HarmonyOS devices as soon as it is available for the device model
• Restrict installation of applications to vetted, trusted sources through MDM policy
• Remove untrusted third-party applications from devices that cannot be patched immediately

Patch Information

Huawei addressed CVE-2026-24919 in the February 2026 security bulletin. Patch availability depends on device model and carrier distribution timelines. Administrators should consult the Huawei Security Bulletin for the specific firmware versions that contain the fix and apply updates through the device's system update mechanism or MDM-managed update channel.

Workarounds

• No vendor-supplied workaround is documented; patching is the primary remediation
• Limit device exposure by enforcing application allowlists and disabling sideloading via MDM policy
• Educate users to avoid installing applications from untrusted sources until the device is updated

# Example MDM policy check: list installed packages on a connected Huawei device
# and flag non-system packages for review prior to patch deployment
adb shell pm list packages -3